I is another letter with two different sounds, the most obvious of which is the long I (ice, island). It is the short I sound, however, that most beginning readers encounter in simple text (is, it, in, big).The following game is useful for solidifying this sound, as well as reinforcing the ability to hear sounds in order.

With a set of magnetic alphabet letters and a cookie sheet, form the word "big". Say each SOUND as you slide the corresponding letter up, identify /i/ as the medial sound. Next, ask what would happen if the /b/ were replaced by /p/ (careful to always refer to the sound, not the letter name). Say the sounds in sequence as you push the letters upward on the cookie sheet. By changing one sound each time, you can create an endless chain of words, each containing the short /i/ sound (big-pig-wig-win-fin-in-it-hit-mit....).
the repetition of the short /i/ sound (coupled with the visual reinforcement of seeing the letter moved each time along with the sound) will solidify it in your child's mind. This technique is useful for drilling other letter sounds as well, and it's very effective for training a beginning reader's eyes and ears to hear and see the sequence of sounds in a word.

It's right after H and comes right before J
I'm talking 'bout the letter named I
And its sound is the same as the one in its name
Come on now, let's give it a try

It's in i-i-i-icicle, bi-i-i-icycle
Why don't you give it a try
It's in i-i-i-i scream and you scream for ice cream
I'm talking 'bout the letter named I

But I does much more than just say its own name
Sometimes it makes a different sound
In words such as sniff and in, it, and if
The letter I sure gets around

It's in i-i-i-igloo and i-i-i-it, too
And hippo and zipper and flip
And i-i-i-if you remember this sound too
Then you can spell hip, dip, and lip

But don't forget I can say i-i-i-island
And ice cube and nice, might, and right
It's a letter that's fun with two sounds, not just one
I'm talking 'bout the letter named I